I have no experience with belt fed weapons. It seems that weather it is a cloth belt or links, the round must be first extracted from the belt, then chambered, no? As a machine designer I see these distinct phases to this operation:
As the bolt opens, draw the round rearward from the belt and move the round from belt alignment to chamber alignment.
As the bolt closes, chamber the round, advance the belt and grab the next belted round.
The goal here is to design a Gattling Gun using .223 Rem. in links.
Regards, Ray

There are a few feed methods for ammo on links/belts/stips.
a) Pull out then chamber, such as MG08, Vickers, 1919.  These actions need more space as the extracted rounds needs to move a few inches up or down to chamber the round.
b) Push thru then chamber, such as MG42, M60, SAW.  The round is pushed out and the next round is set up before the chambered round is fired.  Note there are no push thru belt action as the belt would cause problems.
c) Combined pull and/or push.  A stripper fed action can pull or push the round out.  One particular action actually puts the emptied case back into the stipper clip and eject the spent rounds with the stripper clip as one unit.

If you want to design around the 223 round, then the SAW links is the best choice and it is designed for push thru.  If you use the .45ACP round, it would be a big savings on ammo costs and the cheap M60 links would work.

What gun puts the empty case back in the stripper ?

I would like to see how that works.

The Italian Breda.  Some people think that the empties are put back into the stripper so that for tank use there would be no empties flying into equipment and jamming stuff.  They're a PITA to reloading because the empties have to be pushed out first.